JPS5943603A - Distributed constant type filter - Google Patents

Abstract

PURPOSE:To make effective dielectric constant of dielectrics of each resonator to coincide with each other, by changing a position of a hole for adjusting degree of coupling in a distributed constant type filter. CONSTITUTION:In giving a deviation to a conventional coupling adjusting hole 54 toward the resonator 51 and a conventional coupling adjusting hole 55 toward the resonator 53, the conventional effective dielectric constants epsiloneff1 and epsiloneff2 are changed respetively to epsiloneff1' and epsiloneff2' (epsiloneff1>epsiloneff1', epsiloneff2<epsiloneff2') and a position obtaining epsiloneff1'=epsiloneff2' exists. The coupling adjusting holes provided at this position are 54', 55'. The effective dielectric constants of the dielectrics of resonators 51-53 are made to coincide by changing the position of the coupling adjusting holes in this way.

Description

[Detailed description of the invention] This brother's work concerns a distribution-determined filter with three or more stages.

Conventionally, the filter used was 1 [] (] kAHZ Castle.”
C, LO' (withdrawal!8 or cavity resonator), but structurally unstable I^ is complex or temporally unstable. There were problems such as being unsatisfactory (heh), it took a lot of effort to make adjustments, and the cost could not be reduced (hah).

Therefore, as shown in FIG. 1, %J%'B3. The through holes 12 and 13 of the heavy body block 11 are provided, and a conductive film 14.15 is provided on the inner surface of these through holes 12.1.
r)<, ¥16 is provided, and z, l sunk into the inner surface of the through hole 12.13]1. The heavy films 14 + 15, the conductive film 16 provided on the dielectric block 11, and the dielectric block 11 interposed between them form a coaxial coaxial device in which a solid layer exists between the inner and outer conductors. A pair of coaxial i
A coupling degree adjustment hole 17 is provided in the dielectric lock 11 t'+ls between the front plates, and on the other hand, a tough J path and the above-mentioned resonance unit, j-
There is a distributed constant type filter having an equivalent circuit as shown in FIG. 2, in which the input coupling capacitor 18 and the output coupling capacitor 19 are statically coupled.

・'f) 2 in figure 1/-I'C1216'' two-power terminal, 22 is the output terminal, 26 is the input coupling capacitance tit,
24t, output coupling, 25, 26 u E,'
The 4-wavelength co-imaging circuit jllδ is shown in C as a constant collection circuit in Sakanaka. Therefore, in the distributed number filter 1 in Figure 1, the '/' wavelength resonant circuits are inductively coupled to each other, and the external N
This is a filter in which a path and a 1/4 wavelength resonant circuit are capacitively coupled.

Since such a two-stage distributed constant filter exists,
Naturally, it is conceivable that this can be developed to construct a distribution-limiting, heptagonal filter with three or more stages.

FIG. 61 shows an example of a three-stage case. Go to figure 1, 5
1 is the coaxial resonator of the first stage, 52 is the same IQb resonator of the second stage, and 53 is the same Φ111 resonator of the third stage. 54 is a coupling adjustment hole between the first stage and the second stage, 55
is a coupling degree adjustment hole located between the second and third stages. With such a structure, the coupling adjustment holes 5, 4, and 55 are provided on both sides of the second-stage coaxial resonator 52, but in the coaxial resonators 51, 53 of the first and third stages, there are holes on one side. There is only a coupling adjustment hole 54 and a convex protrusion 55 (1).From this unbalanced state, the second stage 1'
Effective dielectric constant εeff2balu l of di-1i body of 2
and the effective permittivity εQ of the triplex 1゛1 coaxial resonator 51.53
rf Less than H; becomes a value of 11-1. However, up to Part 1, the resonant frequency of the second stage resonator 52 becomes high lq, which becomes an obstacle to obtaining filter stretch. As for that zt strategy [Second stage co-gull'Any 5
Set the resonance frequency of ':' to the first and third stages' IlI←:
= 51, to make it equal to that of S3, J(
It is conceivable to change the material of only the dielectric part of 1.P:, s2 to increase the effective 1.5 current or to make it longer as shown in Figure 4, but this is not practical. Therefore, the object of this invention is to match the effective permittivity of the dielectric material of each resonator.

The gist of this invention is to form three or more cylindrical holes at intervals of 1^'C in a dielectric block, form an inner conductor on the inner peripheral surface of the holes, and form a dielectric body 7. By forming an outer conductor on the west side surrounding the above-mentioned hole of the lock and providing a coupling adjustment hole between the inner conductors, multiple coaxial resonators are inductively coupled to form a distributed constant filter (C1 coupling). The purpose is to match the effective dielectricity 4k of the dielectric of each resonator by changing the position of the degree adjustment hole.

An embodiment of the present invention will be described below with reference to the drawings. Note that the same parts as last time will be marked with 1-double symbols.

Conventional degree of coupling) l・"The hole adjustment 54 is close to the common limiter 51,"
! If fc and the conventional coupling degree adjusting hole 55 are shifted closer to the 1st axis unit 53 and C1^, the conventional effective dielectric constant =
aff, kaεoff,'(CI3ff,〉εe:,'
f,') D. The conventional effective permittivity εeff2 is εegof
4'(=Gff2+-'Qrf2') K becomes εe
There is a position where ff, '-ε5ff2'. The degree of coupling adjustment holes provided at this point are designated as 54' and 55'.

Fig. 6 shows an example of a four-stage, 14-coupling case, which is similar to a three-stage, one-coupling case, in which the conventional coupling degree adjustment holes 65 and 67 are shifted toward the mutual lifters 61 and 64, respectively. 'C1^, the conventional effective rJ rll rate ε9ff, Ka ε-+ff+'(aef
f+>εeff,')(,4 Conventional (7") 11 Effect induction t
li rate εaff, Ka εeff2'(ceff,!<.e
ff2') Nisu, εeff, 1'-=+:ef f2
' There is an r standing 4.

The coupling adjustment holes 1 and 65' and 67' are inserted at this position. As described above, the present invention is effective for filters having three or more stages.

Note that the position of which coupling degree adjustment hole is changed is arbitrary. 4゜Also,
This invention applies not only to the distributed constant type filter of the Comoline type described in the embodiment, but also to the 6+ type of interdigital type filter.
It can also be applied to a 15 constant type filter.

As is clear from the above embodiments, the present invention provides three or more cylindrical holes in a dielectric block at intervals of 14-[
and forming an inner conductor on the inner peripheral surface of this hole,
Form an outer conductor on the west side surrounding the above hole of the dielectric block.
~, 1w' (by changing the vertical position of the coupling degree adjustment hole, each Since the effective dielectric constants of the dielectric bodies of the resonators are matched, the effective dielectric constant of each resonator can be easily adjusted without making the shape of the dielectric block uneven or changing some of the materials. By taking this idea one step further and actively changing the setting point 14 of the coupling adjustment hole, the effective permittivity of each resonator can be made to match.
Any value different from eight can be defined.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional distributed constant filter.
'K Figure 2 is -■ Figure 1's part I [4 of constant J1
In both circuit diagrams, Figure 4 is a plan view of the filter unit, Figure 4 is a perspective view of the filter unit, and Figure 5 is a diagram showing the implementation of the present invention.
Figure 6 shows the planar plane of lJ (to 1) of one embodiment.
1-6A (□;, f:, Xiongshi body 4 kneaded body 54955
and 65' to 67' are 1t' in total): H14 hole-forming. (♀ Applicant Co., Ltd. ← r t: +, + 4v4 Address No. 5 National Defense 4 Kasumikata Diagram) Otsu Ro-12

Claims (1)

[Claims] (The body block has three or more cylindrical holes spaced apart from each other.)
, -h, and an inner conductor is formed on the inner circumferential surface of this hole, and a filter with a distribution of C on all four sides surrounding the dielectric block's two holes is formed with a degree of C1 coupling. j
, '3 By changing the position of the hole, the induction of each resonator is
) A distribution quadratic error shape filter characterized by matching the effective Jj 'ijj rates of one body.